Newb 350x carb question?

[mdmike]

Hey all, proud "new" 350x owner here, and I've got a question.

My new trike has a stock head pipe with a DG slip on, uni filter, and what I think to be stock jetting. It starts up first or second kick every time I've ridden it and seems to have great power. Here's the problem, after it gets warm it has a low idle and a low-end stumble. It also seems to want to "hang" the revs a little once its warm too.

I also have a 300EX quad I bought as a "parts mule" a while back, that I've been pillaging random stuff from here and there. Through some research on this site, I've come to the conclusion that the 300EX has a 32mm carb on it with an accelerator pump whereas the stock 350X carb is 31mm.

If this is indeed true, and I am in the market for a re-jet/rebuild anyway, what is stopping me from using the 300EX's slightly bigger carb and taking advantage of the accelerator pump? I understand the 400EX carb is the way to go if you're swapping it out, but I've got the 300EX carb on hand and its free :lol:

Edit: To add to this, I'm having a strange problem with the throttle sticking every once in a while too. You can feel the thumb throttle stick at about 1/4 throttle. You can either "push" your way through it, or back off the throttle and "massage" it and it will go back to normal. It doesn't do it all the time, but it is annoying when it happens, and it only does it when the machine is running. More research here has pointed at the bore in the carb being worn. Anyone have any experience with this issue?

Thanks for any insight you guys may have!

MIke

220205

[350for350]

If the carb bore is worn, that could cause your slide to stick. Personally, i have a 400ex carb on mine and it runs great. The dumb thing finally idles now too. Without having ever see a 300ex carb, I don't know why you couldn't use one. I'm sure someone else with more experience will be able to tell you. You probably need to richen up your jetting a little. you are letting more air flow through your engine with the Uni and DG so you need to let more fuel flow through. Hope this helps.

[Queef Chief]

There are a few things to check. Accelerator cable could need lube or be pulled in a bit of a stretch. Secondly, check for vacuum leaks around your intake boot and carb. Third thing that comes to mind when you say it revs a bit too long is there is extra fuel getting by... I had this happen to a 200x that sat a long time, and had some pitting on the main needle and main jet seat. After rebuilding the carb, this symptom went away. Have you read your plug? Also, have you had the carb apart to give it a good cleaning? Maybe the slide has some residue on it that is over powering the spring, and causing it to be sticky.

[mdmike]

Thanks for the reply's guys.

I know I have some tinkering to do as far as jetting goes. I have a 660 Raptor quad (twin carbs and very finicky), so I have a little experience with jetting. That being said, I haven't done a chop yet to read the plug.

"350for350", what mods do you have done to your X? Were you able to simply throw the 400EX carb on and ride, or did you have to play with the jetting? I've read of guys being able to wrench the 400 carb on and their machines run great, and others having a heck of a time getting the jetting right.

It looks to me like the throttle cable on the bike may be new. All the metal parts are nice and shiny, and the adjuster by the thumb throttle adjusts easily. There aren't any cracks in the cable or anything like that. Almost makes me wonder if the previous owner was chasing down the sticking throttle and started with a new cable.

I was going to pull the carb off, regardless, since the machine is new to me and I want to have it nice and clean so I have a good baseline to start with. My thinking was, if I have what would be considered an "upgrade" sitting there collecting dust, I may as well start with that instead of the 30 year old stocker.

If I have time this weekend, I'll pull both carbs off of both machines and see what I have.

Thank you guys for the advice, it is much appreciated!

MIke